Pneumatic thermostat.



C. E. BONNET.

PNEUMATIG THERMOSTAT.

APPLIUATION FILED MAY 21, 1909.

Patented Nov. 1, 1910.

WITN ESSES:

- Toallwlwm 'it may concern: e 4

Be itknown that I, CHARLES E. BONNET, b

CHARLES BONNET, F PHILADELPHIA, IENNSYLVANIA.

PNEUMATIC THERMOSTAT.

of Philadelphia, in the State of Pennsylvania, have invented a certain new and useful Improvement in Pneumaticv Thermostats, whereof the following is a speciication, reference being had to the accompanying drawing. t

My device is particularly applicable to regulate the temperature local to it, by means of compressed air arranged to operate a motor in accordance with variable movement of a thermostatic element; said motor bein for instance, operatively related to a va ve on a steam radiator, or to a damper in a Vpipe supplying air of predetermined temperature to the room in which the thermostat is located.

As hereinafter described my invention includes a` casing connected between a source of compressed air and such a motor, andhaving opposite conical valve seat ports,'re spectively'arranged to admit compressed air to said teml erature controlling motor, and exhaust it rom said motor to the atmosphere. A double needle valve havingopposite conical ends, being fitted to said ports,

so that in accordance with reciprocatory movement of said valve, said ports are alternately opened and closed; when said valve is moved 1n one direction, air 1s admitted to operate said "n1otor,.and, when said valve is moved in the opposite direction the motor air-11s exhausted lto permit reverse movement offsa-id motor; them'ovement of said valve befg sette-d in 0m-,direction by the ther;

mostatic element and in tiony by a spring. t t

My invention includes the various novel and arrangement 4hereinafter more definitely specified.

the opposite direc- The drawing shows a vertical sectionaly .view'of a thermostat embodying my improvement.

In said ,drawingt the late 1 is provided ,with suitable means, suc

as screws 2, for attaching it to the wall 3. The casing-5 which .isv supported. by said plate 1 is convenientl attached to the latter by the'tubes 6 and whichlead respective y from a' source of compressed air and. to a tempera-l ture controlling motor, the latter being for instance, a diaphragm valve on. a steam radiator in the room where the thermostat is located, or a spring, pressed diaphragmoperatively connected 'with a damper in the pipe Specification of Letters Patent. 'Patented NOV. l, 1910. Application mea may 21, 1909. serial No. 497,561.

supplying hot air to said room. The chamtively in communication with said source of compressed air and motor, and said chamber 10 has respectively opposite inlet and exhaust parts 11 and 12, the former leading from said chamber 9 and the latter leading to the outer atmosphere through an adjustable screw threaded plug 14, whereby the spaced' relation of said seats may be adjustably predetermined. The double needle valve 15 has opposite conicalends 16 and 17 respectively fitted to said port's 11 and 12, so that in accordance with reciprocato movement of said valve, said ports are a ternately opened and closed. The lever 2O which is fulcrumed on the pin 21 in the lugs 22 on said casing 5 is arran ed to shift said valve A15 to close said et port 11 under pressure of the s' ring 24 which is attached at one end to sald lever by the screw and, bears upon the casing at its opposite end. The spring 27 arranged in concentric relation with said valve 15 tends to shift the latter to close the exhaust port 12, but is weaker than the spring 24, so that when the latter is unrestrained said lever 20 is shifted to close the inlet port 11. However, said stronger spring 24 1s normally restrained to permit said weakerspring 27 to normally maintain'said'valve 15, closing said exhaust port 12in the position shown in the drawing, b the thermostatic element including the cyli ndrical tube of hard'rubber 30, havers 9 and v10 in said casing 5 are respecing the metallic cap 31 recessed at 32 so as to pvotally engage the lower end of said screw 25. Said thermostatic tube 30 maybe adjusted in its relation to the lever 20 and the springs aforesaid, by means arranged to raise and lower said tube 30, including the f metallic base- 35 whichosu:l ports said tube 30, and has the screw'36 tted in the base flange of the casing 5. Said base 35 may be conveniently raise and lowered by theindex lever 37 which is threaded at its inner end to `lit said screw 3 6, and is adjustably and detachably connected therewith by the set screw 38.A The free end of said lever extends through the slot 40 in the cover 41 and has the index point 42-extending in coi operative relation with a suitable scale of temperature graduations upon the exterior Y ferent temperatures in accordance with-the j adjustment of said lever 37 with respect to said temperature scale. Said cover 41 is conveniently formed of pressed sheet metal perforated to permit access of the atmosphere -to the thermostatic element aforesaid, and is detachably connected with said casing by means of the screws 45.

The device above described operates Aas followsz-In the position shown in the drawing'the exhaust port 12 being closed and the inlet port 11 opened, compressed air is admitted through the tubes 6 and 7 to the temperature controlling motor connected with the latter so as to hold said motor in the desired position to maintain the temperature corresponding with the position of the lever 37. However, if the temperature in the room containing said device becomes .embodiment of my invention, wherein the thermostatic elementA includes a cylindrical tube of hard rubber, it is to be understood that a suitable thermostatic element may be "made of other form and material capable of effecting the desired operation of said lever and valve. Therefore, I do not desire to limit myself to the recise details of construction above descri edas it is obvious that various modifications maybe made therein `without departing from the essential features of my invention as defined in the Aa. pended claims.

I c aim 1. The combination with a casing having respectively opposite conical valve seat inlet and exhaust ports; of a double needle valve having opposite conical 'ends respectively fitted to said ports, so constructed and arranged that in accordance with reciprocatory movement of said valve said ports are alternately opened and closed: a lever ar'- ranged to shift said valve to close saidin.

let port; a strong spring'arranged to operate said leverto close sald port; a weaker spring tending to shift said valve to close said exhaust port; a thermostatic element normally restraining said stronger spring and permitting said weaker sprinu to .nor-

mally maintain saidvalve closing said exhaust port; said thermostatic element- 1' Y cluding a cylindrical tube of hard rubber having a metallic cap operatively engaging said lever, a metallic base havin means arranged to raise and lower. it, including a screw fitted in said casing, an index lever adjustably connected with said base,.and means detachably connecting said lever and base; whereby, said thermostaticI element may be adjusted to operate said valve at different temperatures.

2. The combination with a. casing having respectively opposite conical valveseat inlet and exhaust ports; of a double needle valve having oppositeconical. ends respectively fitted to said ports, so constructed and arranged that in -accordance with reciprocatory movement of said valve said ports are alternately opened and closed; a leverarranged to shift said valve to close said inlet port; a strong spring arranged 'to operate said lever to Vclose said port; a weaker spring tending to shift said valve to close said exhaust port; a thermostatic element normally restraining said stronger spring and permitting said weaker spring to normally maintain said valve closing said'exliaust port; said thermostatic element including a hard rubber tube having means operatively engaging said lever, a metallic base having means arrangedvto raise and lower said tube, including a screw, an index lever connected with said, screw, and means detachably connecting saidilever and screw;

whereby, said 'thermostatic element may be adjusted .to operate said valve at different temperatures.

3. The combination with a-casing having respectively opposite conical valve seat in-- let and exhaust ports; of a double needle valve having opposite conical ends respectively fitted to said iports, so constructed and arranged that in accordance with re- 'ciprocatory movement of said valve said port-s are alternately opened andelosed; a lever arranged to shift said valve to close said inlet port; a strong spring arranged to operate said lever to close said ort; a weaker spring tending toshift sald valve element normally restraining said stronger spring and permitting said weaker sprmg to normally maintain said valve closing said exhaust port; said thermostatic element including a hard rubber member having means operatively engaging said lever, means ardifferent temperatures.

4. The combination'with a=casing having respectively opposite conical valve seat inlet and exhaust ports; of a double needle valve having .opposite conical ends respectively fitted to said ports, so constructed and arrangedthat in accordance with reciprocatory movement of said valve said ports are alternately opened l and closed; a lever arto close said exhaust port; athermostatic ranged to shift said valve to close said inlet port; a strong spring arranged to operate said lever to close said inlet port; a weaker sp-rinc1r tending to shift said valve to close said exhaust port; a'thermostatic element normally restraining said stronger spring and permitting said weaker spring to normally maintain said valve closing said exhaust port; said thermostatic element including a hard rubber member having means operatively engaging said lever, and, means arranged to raise and lower said member; whereby, said thermostatic element may be adjusted to operate said valve at different temperatures.

5. The combination with a casing having- -respectively opposite valve seat inlet and exhaust port's; of a double needle valve having opposite ends respectively fitted to said ports, so coiistiucted and arranged that in accordance with ieciprocatory movement of said valve said ports are alternately opened `and closed; a lever arranged to shift said valve to close said inlet port; a strong spring arranged to operate said lever to close said inlet port; a weaker s ring tending to shift said valve to close sai exhaust port; a theriiiostatic element normally restraining said stronger spring and permitting said weaker spring to normally maintain said valve closing said exhaustport; said tliermostatic element including a hard rubber member having means operatively engaging said lever,v

and, means arranged kto raise and lower said member; whereby, said thermostatic element may be adjusted to operate saidl valve atdifferent temperatures.

6. The combination with a casing having', respectively opposite conical valve seat inlet and exhaust ports; of a double needle valve having opposite conical ends respec.k

tively fitted to said ports, so constructed and arrangedthat in accordance with reciprocatory movement of said valve said orts are' alternately opened and closed; a ever arranged to shift said valve to close said inlet port; a strong spring arranged to operate said lever to close said inlet port; a weaker spring tending to shift saidl valve to close said exhaust port; and, a thermostatic element expansively restraining said stronger spring and permitting said weaker spring to normally maintain said valve closing said exhaust port; said thermostatic element being arranged to expansively thrust said lever to operate it.

7. The combination with a casing having respectively opposite valve seat inlet and exhaust ports; of a double valve having opposite ends respectively fitted to said ports,

so constructed and arranged that in accord-.

ance with reciprocatory movement of said valve said ports are alternately opened and closed; a lever arranged to shift said valve to close said inlet port; a strong spring arranged to operate said lever to close said inlet port; a weaker spring tending to shift said valveto close said exhaust port; and,

a thermostatie element expansively restraining said stronger spring and permitting said weaker spring to. normallyI maintain said valve vclosing said exhaust port; said thermostatic element being arranged to expan- 1 sively thrust'said lever to operate it.

In testimony whereof, I have hereunto signed my name at Philadelphia, Pa., thiseighteenth day of May, 1909. CHARLES E. BONNET.

Witnesses:

ARTHUR E. PAIGE, CATHARINE C. CAssIDY. 

